Weekly images of sea surface temperature (SST) have been constructed for the tropical Atlantic Ocean for May‐September, 1984–1990, from National Oceanic and Atmospheric Administration National Environmental Satellite, Data, and Information Service satellite‐derived sea surface temperature data. These images have been analyzed to determine weekly to seasonal changes in the position of the fronts between the cold equatorial water and the warmer waters to the north and south. We have found that long waves along the northern front (previously reported by Legeckis and Reverdin (1987)) are present each year, although their number, strength, and duration vary. The year 1987 was the most atypical, with only a few short‐lived waves seen. The long waves typically appear in SST in mid‐June and last into September. They form along the equatorial thermal front between 5°W and 30°W and propagate westward, sometimes reaching 45°W. Wave crests travel at speeds varying between 10 and 40 cm/s, but variations in amplitude reveal that the group velocity of the waves is eastward at 30 cm/s. Long‐wave crests are observed to be associated with mesoscale anticyclonic warm‐core eddies, which apparently play a significant role in cross‐equatorial heat transport. Instability features are also observed along the southern front of the equatorial cold tongue, although because of weaker thermal gradients they are less distinct. Southern waves propagate westward along the front at speeds and wavelengths similar to the long waves in the north. There is no simple phase relationship between long waves and the southern waves, which suggests that the southern waves are not the direct result of the northern long waves.
Candela et al. (1990, 1992) showed that tides in an open ocean region can be resolved using velocity data from a ship-mounted ADCP. We use their method to build a spatially varying model of the tidal currents in the Gulf of the Farallones. an area of complicated bathymetry where the tidal velocities in some parts of the region are weak compared to the mean currents. We describe the tidal fields for the M 2 , S2, K,, and 0, constituents and show that this method is sensitive to the model parameters and the quantity of input data. In areas with complex bathymetry and tidal structures, a large amount of spatial data is needed to resolve the tides. A method of estimating the associated errors inherent in the model is described. Published by
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.